Fluid production and storage control apparatus



Jan. 29, 1957 RQBERTSQN 2,779,348

FLUID PRODUCTION AND STORAGE CONTROL APPARATUS Filed Nov. 15, 1952 2Sheets-Sheet l i0 INVENTOR.

MELB 6mm ROBERTSON ATToRgmy Jan. 29, 1957 M. ROBERTSON 2,779,348

FLUID PRODUCTION AND STORAGE CONTROL APPARATUS Filed Nov. 1 3, 1952 2Sheets-Sheet 2 H @@N P *WN W Eva m P w mwm $3 M nmm @ML Q mm BER'I S N ERNEY United States Patent FLUID PRGDUCTION AND STORAGE CONTROL APPARATUSMelhorne L. Robertson, Laird Hill, Tex, assignor to Gulf OilCorporation, Pittsburgh, Pa., a corporation of Pennsylvania ApplicationNovember 13, 1952, Serial No. 320,262 39 Claims. (Ql. 137-119) Thepresent invention relates to new and useful improvements in apparatusfor automatically controlling the supply of a fluid to a multiple-unitstorage facility and the sequential filling of selected storage unitswith supplied fluid.

The paramount aim of the invention is to provide a dependency of thefluid supply control upon the automatic storage unit selector of such anature that failure of the selector to select a unit in readiness to befilled, either through malfunction of the selector or the actual absenceof an available unit in readiness to be filled, will cause the fluidsupply control to curtail further fluid supply.

Closely allied to the aim of the preceding paragraph is the desire toprovide apparatus in which the fluidsupply control may be made dependentupon the occurrence of one or more other predetermined events to causecurtailing of the supply of fluid, in addition to failure of theselector to locate a storage unit in readiness to be filled.

Another important purpose of the invention is to provide apparatus ofthe character defined, in which the fluid-supply control may be used toindividually and collectively control the supply of fluid from aplurality of fluid sources, and which fluid-supply control may beoperated in such a manner that the entire supply of fluid from aplurality of fluid sources may be periodically curtailed according to apredetermined time schedule, and/ or the supply of fluid fromindependent fluid sources be periodically curtailed according to apredetermined time schedule for individual fluid sources.

It is a further aim of this invention to provide apparatus of thecharacter defined, in which the fluid-supply control may be associatedwith a fluid source that requires pumping, and which will operate tointerrupt pumping of such fluid source in addition to otherwisepositively curtailing fluid flow through the pumping equipment.

In addition, it is desired to provide a fluid-supply control which maybe operated to curtail the supply of fluid from a fluid source that doesnot require pumping, while operating with respect to a further fluidsource that requires pumpin in the manner set forth in the precedingparagraph.

An important obiect of this invention is to provide apparatus of thecharacter defined, wherein the selection of a unit as being in readinessor filling as Well as the continued introduction of fluid into aselected unit may be made contingent upon predetermined circumstances inaddition to the unit being less than full.

It is also an object of this invention to provide automatic electriccontrol apparatus that is well adapted for the incorporation ofindicator lights therewith in such a manner as to require a minimum ofadditional wiring and yet afford valuable information as to the state ofoperation of the apparatus.

Still another object of this invention is to provide apparatus of thecharacter defined, which, in addition to having fields of utility inother industries, is parti lariy well suited for use in producing oilfields; and which in such an environment will care to automatically andsequentially select and flll so tanks of a tank battery that are inreadiness to be fii which will also serve to shut in individual pumpingflowing oil Wells in accordance wi h predeter -ued time schedules; andwhich will shut in all oil wells supplying the tank battery upon failureof the tank selector e her to select a tank.

for filling or upon one of the oil-treating units normally interposedbetween the wells and the battery becoming excessively full.

inasmuch as it is contemplated that the probable major field of use ofthe invention will be in controlling oil field production and storage,the invention has been illustrated as applied to such a use in theaccompanying drawings, wherein:

Figure l is a schematic illustration of an oil producing and storagefacility including oil wells, oil-treating units, a tank battery andassociated flow-control equipment, together with a diagrammaticrepresentation of the control apparatus of this invention appliedthereto;

Figure 2 is a top plan view of a rotary switch shown as part of thecontrol apparatus of Figure l; and

Figure 3 is a diagrammatic representation of a modifled form or" aportion of the apparatus shown in Figure l.

Broadly speaking, the invention comprises three cooperating parts,namely, what may be conveniently termed a tank selector and switcher,oil well producing equipment, and apparatus for curtailing production.Each of these parts will be individually des;ribed and their cooperationexplained hereinafter. it is believed that a more ready understandingwill be obtained with a brief introductory recital of the functions ofthe three parts of the invention.

Accordingly, that portion of the invention termed the tank selector andswitcher serves upon completion of the filling of one tank to close theinlet valve thereto, locate another tank in readiness to be filled, andto open the inlet valve thereof. A preferred and an alternative form ofthis portion or" the invention are illustrated and described.

The oil well producing equipment serves to produce and to individuallyshut in both flowing wells or wells to pump or other artificial liftingdevices. Such equipment serves to produce and shut in individual wellsaccording to a predetermined time schedule or each well, but will, inaddition, serve to shut in all the oil wells in accordance with apredetermined master time schedule and is also subject to the control ofthe production curtailing apparatus.

The production curtailing apparatus functions in addition to the timeschedule to cause the oil well producing equipment to shut in all theoil wells upon the occurrence of either of two events, namely, upon thefailure of the tank selector to select a tank .(Ol filling within anadequate period of time, or upon any oil treating vessel interposedbetween the oil wells and the tank battery becoming excessively full.

Tank selector and switcher Attention is first directed to the form ofthe tank selector and switcher illustrated in Figures 1 and 2, whereinthe numerals 1t), 12 and 14 designate diagrammatic representations ofoil storage tanks of a multiple-tank battery. The tanks 10, 32 and aresupplied oil from a header 16 by means of individual tank branches 18,2t and 22, respectively, and are emptied through individual outlet pipes24, 26 and 28, respectively, to a discharge line 3%.

In order to control the supply of oil to individual tanks, the tankbranches 1%, 2d and 22 are provided with electrically-actuated inletvalves 32, and 36, respectively.

The electrically-actuated valves 32, 34 and 36 are of conventional twoposition type and are of such character that upon being energized willopen and upon being tie-energized will close. Known valves of the typeinvolving the use of an electric motor and hydraulic valve-moving meansare preferred for such purpose, although solenoid-actuated valves mayalso be used.

The outlet pipes 24, 26 and 28 are provided with valve and electricswitch assemblies 38, 4t and 42, respectively, which are of a known typein which the electric switch opens and closes with the valve. Thus, whenthe assembly 38 is operated to permit fluid flow in the outlet pipe 24,the switch component thereof is opened.

The tanks 10, 12 and 14 are also provided with liquidlevel sensitiveswitch assemblies 44, 46 and 48, respectively, of such a character thatthe switch of any particular switch assembly is closed whenever theliquid in its associated tank is below a predetermined level. Theassemblies 44, 46 and 48 are preferably of the conventionalfloat-actuated type, but may be of other known types, such as fluid headpressure-actuated switches, etc.

Solenoid actuated, double pole double throw relay switches schematicallyillustrated at 50, 52 and 54 are provided for association with the tanks10, 12 and 14, respectively. Each of the switches are identical inconstruction, and it is thought that a detailed description of one willsufiice for all. The switch 50 includes a first pair of contacts 56 onthe right of switch 513 as shown in Figure 1 that are normally bridgedby a blade 58 biased thereagainst, and a second pair of contacts 60 onthe left of switch 50 as shown in Figure 1 that are bridged by themovable blade 58 when the solenoid 62 of the switch 50 is energized.

A three-phase power source 64 is provided to which power leads 66, 68and 70 are coupled. Power for the tank selector and switcher is takenfrom power leads 66 and 68, with the voltage adjusted to the desiredlevel by means of a transformer 72. The primary of the transformer 72 isconnected to the power leads 65 and 68 as shown, and the secondarythereof is coupled to the electric conductors 74 and 76 through whichelectrical energy is made available to the tank selector and switcher.

A rotary switch assembly is designated generally at 78. Such switchassembly 78 is illustrated diagrammatically and includes anelectrically-actuated prime mover 8i drivingly connected to a rotatabledisc 82. The disc 82 is fashioned of electrically-insulating material,such as plastic, and is provided with a recess in its upper surface inwhich a sector 84 formed of electrically-conductive material, such ascopper, is suitably secured. The arrangement is such that the disc 82may be rotated by the prime mover 89 so that the sector 84 mayselectively bridge the pairs of stationary contacts $6, 83 and 90 thathave sliding contact with the upper surface of the disc 82, as clearlyshown in Figure 2.

The dimensions of the sector 34 are such with respect to the angularspacing of the pairs of contacts 86, 88 and 90 that the sector 84 maybridge the contacts of only one pair of contacts at any one time. Inaddition, the prime mover 80 is of such a type that the disc 32continues to rotate for only a fraction of the angle subtended by thesector 84 at the center of the disc after the prime mover 80 isde-energized. Preferably, the prime mover 80 is an electric motorprovided with reduction gearing, whereby the disc will be driven at alow speed, say in. the order of one revolution per minute. Thus, iftheprime mover Stl is de-energized shortly after the sector 84 bridgesone of the pair of contacts 86, 88 and 94],. the disc 82 will stoprotation while such pair of contacts remain bridged.

One power lead 92 of the prime mover 30 is connected to the electricconductor 76, and the other power lead 94 is connected in series withthe normally-bridged right pair of contacts of all the switches 59, 52and 54 to the other electric conductor 74 by means of conductors:

96, 98, 180 and 102, as clearly shown in Figure 1. The arrangement issuch that as long as the right pair of contacts, such as contacts 56 ofswitch 50, of all the switches 50, 52 and 54 are bridged; a circuit,which for the purpose of the claims will be called the selector circuit,is closed between the conductors 74 and 96 and through the prime mover80 thence to the line 76. However, energization of the solenoid of anyof the switches 54 52 and 54, such as solenoid 62 of switch 56 willcause the blade thereof to move from a position bridging the right pairof contacts of such switch and thereby open the selector circuit andde-energize the prime mover 80.

Circuit means are provided for each of the tanks 10, 12 and 14, wherebythe solenoid of one of the switches 50, 52 and 54 associated therewithmay be energized. Such circuit means are identical for each tank, and itwill suffice to define only such circuit means relating to tank 1t) andto switch 50 in detail. Such particular circuit means comprises oneterminal of the solenoid 62 being connected to the conductor 74 by meansof leads 1G4 and 1%, while the other terminal of the solenoid 62 isconnected to the other conductor 76 in series through the pair ofcontacts 86, a manual switch 1&8, the liquid-level sensitive switch 44and the valve and switch assembly 38 by means of leadsc Hit, 112, I114,116, 118 and 120, as shown.

It will therefore be apparent that whenever switch 108 and the switchcomponents of the liquid-level sensitive switch 44 and the valve andswitch assembly 38 are closed, bridging of the contacts 86 by the sector84 will result in energization of solenoid 62. As mentioned previously,energization of the solenoid d2 will cause the blade 58 to move from aposition bridging the right pair of contacts 56 to a position bridgingthe left pair of contacts 6%, thereby opening the selector circuit thatincludes the prime mover 80.

As stated hereinbefore, circuit means such as those described in thepreceding paragraph in connection with tank 113 and switch 50 isprovided for each of the tanks 12 and 14 and their associated respectiveswitches 52 and 54. The operation of these other circuits is preciselythe same as that of the described circuit and their operation may besummarized by stating that bridging of the pairs of contacts 88 and 969by the sector 84 will result in energization of the solenoids of theswitches 52 and 54, respectively, whenever the associated switches inseries therewith are all closed, such as manual switch 122, liquid-levelsensitive switch 46 and the switch component of the switch and valveassembly 40 which are in series with the pair of contacts 853.

In summary, it may be stated that with respect to the solenoid of eachof the switches 50, 52 and 54, a number I of conditions are necessarybefore the same may be energized, namely, the sector 34 must bridge thepair of contacts associated therewith, and the manual switch, theliquid-level-sensitive switch and the switch component of the valve andswitch assembly associated therewith must all be closed. Since thesector 84 may only bridge one of the pairs of contacts 86, 88 and at onetime, it will be evident that only one of the solenoids of the switches50, 52 and 54 can be energized at any one time. Furthermore, since theliquid-level sensitive switch associated with each of the tanks isarranged to be closed only when the liquid level in the tank is below apredetermined level, and since the switch element of the associatedvalve and switch assembly is closed only when the outlet of such tank isclosed, it will be evident that the solenoid of the switch associatedwith such tank may be energized only when the outlet of such tank isclosed as well as the tank being filled to a level less than thatnecessary to close the liquid-level sensitive switch.

An inlet-valve actuating circuit is provided for each of the tanks, andinasmuch as the valve-actuating circuits are identical, only suchcircuit provided for actuating the inlet valve 32.0)? tank 10 will bedescribed in detail. The

3 inlet-valve actuating circuit provided for tank includes in series thesecond pair of contacts 60..of the switch 50 and theelectrically-actuated inlet valve 32, such circuit comprising onecontact of the pair of contacts 60 being connected to the conductor 74by means of leads 104 and 106, with the other contact of such pair ofcontacts 60 being connected to one of the terminals of theelectricallyactuated inlet valve 32 by lead 124. The other terminal ofthe electrically-actuated inlet valve 32 is connected to the conductor76 by means of lead 120. Thus, whenever the blade 53 of the switch 50 isactuated by the sole noid 62 to bridge the pair of contacts 60, thevalve-actuating circuit associated with the electrically-actuated inletvalve 32 is closed, whereby the inlet valve of tank 10 is opened.Similarly, the valve-actuating circuits of tanks 12 and 14 include theelectrically-actuated inlet valves 34 and 36, respectively, whichelectrically-actuated inlet valves 34 and 36 are respectively coupled inseries through the second pair of contacts of their associated switches52 and 54 to the electrical conductors 74 and 76.

Viewed in its broader aspects, the inlet-valve actuating circuits thatinclude the electrically-actuated inlet valves 32, 34 and 36 may beconsidered controlled circuits, with the circuits that include the pairsof contacts 86, 88 and 90 and the solenoids of the switches 50, 52 and54 being considered control circuits. In accordance with this view,energization of any of the control circuits serves through the agency ofthe switches 50, 52 and 54 to open the selector circuit and to controlthe closure of one of the controlled circuit.

In summary, bridging of the respective left pair of contacts of any oneof the switches 50, 52 and 54 will close a circuit through theelectrically-actuated inlet valve of the associated tank, so as to openthe inlet thereof.

The operation of the tank selector and switcher will be readilyunderstood from the following explanation thereof.

As a starting point, it will be assumed that all of the tanks 10, t2 and14 are empty and that the outlets thereof are closed and in additionthat all of the manual switches corresponding to switch 108 are closed.Furthermore, it will be assumed that the sector 84 is not bridging anyone of the pairs of contacts 86, 88 and 90. Under such circumstances, itwill be evident that none of the solenoids of switches 50, 52 and 54 areenergized and that the blade elements of each of the switches 50, 52 and54 are bridging the right-hand pair of contacts thereof. The bridging ofthe right pair of contacts of switches 54 52 and 54 completes thecircuit through the prime mover 86 with the result that the disc 82 isrotated.

Such rotation of the disc 82 will bring the sector 84 into a positionthat will bridge one of the pairs of contacts 86, 88 and 99, which wewill assume to be the pair of contacts 86. Inasmuch as the switch 108 isclosed, and by virtue of the fact that the tank 10 is empty and theoutlet-valve thereof closed, the switches associated with theliquid-level sensitive switch 44 and the valve and switch assembly 38are also closed, with the result that bridging of the contacts 86 by thesector 84 completes the circuit through the solenoid 62. Completion ofthe circuit through the solenoid 62 energizes the same and causes theblade 58 to move from a position bridging the right pair of contacts 56to a position bridging the left pair of contacts 6'9 to produce atwofold result. In the first place, movement of the blade 58 from aposition bridging the contacts 56 opens the selector circuit through theprime mover 30 which stops rotation of the disc 82 and leaves the sector84 in a position bridging the contacts 86. in the second place, bridgingof the left pair of contacts 69 by the blade 53 completes thevalveactuating circuit associated with tank 10, thereby energizing theelectrically-actuated inlet valve 32 of tank It) to open position.

The electrically-actuated inlet valve 32 will remain energized to permitfilling of tank 10 so long as the solenoid 62 is actuated. Eventuallytank 10 will become sufficiently filled with liquid that theliquid-level sensitive switch 44 will open with the result of openingthe circuit through the solenoid 62, whereupon such de-energization ofthe solenoid 62 will result in the blade 58 moving from a positionbridging the left pair of contacts 60 to a position bridging the rightpair of contacts 56 with a twofold result. Such movement of the blade 58will open the circuit through the electrically-actuated inlet valve 32and close the selector circuit through the prime mover 30.

As soon as the prime mover is energized, the disc 82 is rotated to aposition in which the sector 84 bridges the pair of contacts 88, withthe result that the solenoid associated with switch 52 is energized,with such energize.- tion of the solenoid opening the selector circuitand closing the circuit through the electrically-actuated inlet valve34. As in the case of the filling of tank 10, the filling of tank 12 toa predetermined level breaks the circuit, by means of the liquid-levelswitch 46, through the solenoid of the switch 52 to thereby de-energizethe electrically-actuated inlet valve 34 and again close the selectorcircuit through the prime mover 80.

in an analogous manner, the automatic sequential filling of tank 14 isaccomplished.

The above-described operation would be somewhat different had say, forexample, tank 12 been initially full, the manual switch 122 open, or theoutlet valve thereof open. Had such an initial condition existed, thecircuit through the solenoid associated with the switch 52 would nothave been completed upon the sector 84 brdging the contacts 88 with theresult that the selector circuit through the prime mover 80 would nothave been interrupted, nor would the circuit through theelectrically-actuated inlet valve 34 have been completed, andaccordingly the disc 82 would have continued to rotate until the sector34 bridged the pair of contacts 99. In such a manner, a tank not inreadiness to be filled is by-passed without even momentary disturbanceof the continuous operation of the prime mover 80 and without themomentary energization of the electrically-actuated inlet valveassociated with the tank to be bypassed.

A tank may be in what may be termed a condition of readiness to befilled only when the solenoid of the switch 50, 52 and 54 associatedtherewith may be energized through action of the selector switch 78. Forexample, tank It) is in the condition of readiness to be filled when themanual switch 183 is closed, the liquidlevel sensitive switch 44 isclosed by virtue of the tank being less than full, and the switchcomponent of the valve and switch assembly 33 is closed by virtue of theoutlet of tank 10 being closed.

It will also be apparent from the foregoing that, if a tank which is inthe process of being filled is inadvertently or otherwise opened to thedischarge line 30 by opening its outlet-valve such as 33, or 42, thiswill immediately open the circuit through leads 116 and 118 for example,which results in breaking the current through coil 62 of relay 50,whereupon the blade 53 moves to the right-hand position bridgingcontacts 56. This completes the circuit to prime mover 89 through leads94 and $6 causing the selector to seek another tank in readiness, thuspreventing flowing into a tank which is open to the discharge line 34 bythe closure of the inlet valve, such as 32, 34 or 36, of the tankconcerned. This function is important because the fluid is gauged, i.e., measured, in the tank.

The requisites that may be imposed upon the condition of a tank being inreadiness to be filled may be multiplied as desired simply by includingadditional switches, not shown, in series with the associated pair ofcontacts 86, 823 and 90; with each of such additional switches beingassociated for actuation with some form of detecting means of theadditional requisite desired to be imposed upon the condition of a tankbeing in readiness to be filled. For example, for fire protectionpurposes, it may be desirable to prevent or interrupt the flow of liquidinto tank 11) when the same is on fire, in which event a thermalresponsive switch, not shown, would be placed in series with the pair ofcontacts 86 and the solenoid 62, which thermal responsive switch wouldbe responsive to temperature in the vicinity of the tank rising above apredetermined value to open.

The manual switches, such as switch 108, provided in series with each ofthe pairs of contacts 86, 88 and affords a means whereby the operatormay by opening such switch cause the associated tank to be by-passedwhenever desired, as when the tank is under repairs or the like.

It will of course be understood that the prime mover 80 rotates the disc82 in such a manner that the sector 84 will sequentially bridge thepairs of contacts 86, 8% and 90. It is important to note that dependentupon the type of prime mover 80 employed, a predetermined period of timeis required for the sector 84 to move from a position bridging any oneof the pairs of contacts 86, S8 and 90, until the same has sequentiallybridged all the other pairs of contacts, and has again been brought intoposition bridging the first pair of contacts, assuming continuousoperation of the prime mover 80. It will of course be evident thatcontinuous operation of the prime mover 80 for a period sufiicient tocause the disc 32 to make a complete revolution can only occur when allof the tanks have been by-passed, or, in other words, whenever none ofthe tanks is selected as being in readiness to be filled.

Advantage is taken of the fact that continuous operation of the primemover 80 for a period of time sufiicient tocause a complete revolutionof the disc 82 can only take place upon the failure of the apparatus toautomatically select a tank in readiness to be filled for the purpose ofcurtailing the supply of liquid to the header 12. The structure utilizedfor taking advantage of this fact involves the use of an electricalswitch which is actuated in ersponse to continuous energization of theprime mover 36 for a period of time at least as great as that requiredfor the prime mover 81) to rotate the sector through contact with allthe pairs of contacts 36, 88 and 90, which period of time may beconveniently referred to as the selector time cycle. Various types ofconventional electrically-actuated switches incorporating a time-delayfeature may be utilized for this purpose. However, the use of atime-delay relay or a so-called Amperite timedelay tube such as thatindicated at 130 is preferred.

The time-delay tube 130 has the coil thereof connected in parallel toprime mover 80 by means of leads 132 and 134 that are connectedrespectively to the leads 92 and 94. The switch element 136 of thetime-delay tube 130 is normally open, but is arranged to close inresponse to continuous energization of the tube 135 through the leads132 and 134 for a time interval equal to or slightly in excess of thehereinbefore defined selector time cycle. Inspection of the drawing willindicate that the parallel arrangement of the time-delay tube 13-1? andthe prime mover 311 causes the tube 131) and the prime mover 89 to beconcurrently energized and deenergized. It will thus be seen thatwhenever the sector 84 has been continuously moved through sequentialcontact with all the pairs of contacts 36, 88 and 9%} without the primemover being deenergized, it may be stated that the tank selector andswitcher has failed to locate a tank in the entire tank battery that isin readiness to be filled. Such continuous movement of the sector 34requires continuous energizetion of the prime mover 8t) and the coil ofthe time-delay tube 130 for the selector time cycle and will result inclosure of the switch 136. Subsequently, reference will be made to theeffect of closure of the switch 136 in connection with the descriptionof the production-curtailing apparatus.

The field of .usev of the hereinbefore-described tank selector andswitcher isgreater than that of merely controlling the storage of oil orother liquids, and may be readily extended to the storage of gases in aplurality of tanks. In the latter use, the extent to which tanks aredesired to be filled may be ascertained by pressure, and in such use, apressure sensitive switch would be employed in connection with each tankin lieu of a liquid-level sensitive switch, with such switch beingarranged to open when the pressure within the tank exceeds apredetermined level. Those familiar with the art of fluid storage willreadily comprehend the adaptation of the described tank selector atndswitcher to the storage of gases.

Before proceeding with a description of the production controllingequipment and the production curtailing apparatus, it is thoughadvisable to describe the alternative form of tank selector and switchershown in Figure 3, which may be used in lieu of the hereinbeforedescribed preferred form of tank selector and switcher. The Figure 3apparatus will be described for oil storage purposes but may also beemployed for other purposes as may that of Figure 1.

The alternative form of tank selector and switcher shown in Figure 3 isshown in conjunction with storage tanks 138, Mt) and 142 whichcorrespond to tanks 10, 12 and 14 shown in Figure 1. The tanks 138, 140and 142 are supplied fluid from a header 1 14 through individual tankbranches 146, 148 and 159, respectively. The tank branches 146, 148 and150 are provided with electrically-actuated inlet valves 152, 154 and156, respectively, such electrically-actuated valves corresponding tothe electrically-actuated inlet valves 32, 34 and 36 shown in Figure 1.

In addition, the tanks 138, 141) and 142 are provided with outlets 158,and 162, respectively. The outlets 158, 160 and 162 are provided withvalve and switch assemblies 164, 166 and 168, respectively, thatcorrespond to the assemblies 38, 4t) and 42 of Figure 1. Furthermore,the tanks 138, 148 and 142 are provided with liquid-level sensitiveswitches 170, 172 and 174 that correspond to the liquid-level sensitiveswitches 44, 46 and 48 of Figure 1.

Solenoid-actuated double-pole-double-throw switches 176, 178 and 189,corresponding to the switches 50, 52 and 54 of Figure 1, are associatedrespectively with the tanks rss, 140 and 142.

A three-phase source of electrical energy 182 is provided having powerleads 184, 186 and 188, with the power leads 184 and 136 being connectedto the primary winding of a transformer 19% that corresponds to thetransformer 72 of Figure 1. The secondary winding of the transformer 190is connected to an electrical conductor 192 that corresponds to theelectrical conductor 74 of Figure 1, while the other terminal of thetransformer 190 is grounded, as at 194, with the ground potential inthis modification of the invention corresponding to the conductor 7 6shown in Figure 1.

This form of the invention also involves the use of a prime mover 196that corresponds to the prime mover 80 of Figure 1. The prime mover 196has one terminal grounded as at 198 and is connected in series throughall the first or right-hand pairs of contacts of all of the switches176, 1713 and 186 to the electrical conductor 192 by means of leads 2%,2132, 204 and 2116, it being understood that the right pairs of contactsof the switches 176, 178 and are normally bridged by the blade elementsof such switch when the solenoids thereof are de-energized. Thearrangement is such that energization of the solenoid of any of theswitches 176, 178 and 180 will open the circuit through the prime mover1% and that subject to an exception subsequently to be noted, wheneverall of the solenoids are de-energized the circuit through the primemover 196 which may be referred to as the selector circuit is closed.

The principal distinct-ion between the alternative form of tank selectorand switcher of Figure 3 and that shown in Figure l resides in themanner in which the solenoids of the switches 176, 178 and 180 areenergized. Whereas the form of tank selector and switcher shown inFigure 1 employs the rotary switch 78 in order to complete the circuitsthrough the solenoids, the alternative form of tank selector andswitcher shown in Figure 3 employs a system of photoelectric circuitsand relay switches to accomplish the same purpose. The alternative tankselector and switcher of Figure 3 involves the use of an electric lampcircuit in association with each of the tanks and the arrangement issuch that the lamp circuit associated with each tank is closed so as tolight an electric lamp in such circuit whenever the tank associatedtherewith is in readiness to be filled. A photoelectric circuit means isassociated with each of the electric lamps in such a manner as to beactuated in response to the associated electric lamp being lighted toactuate an electric relay switch system for energizing the solenoid ofthe associated double-pole-double-throw switch of such tank. Inaddition, means operated by the prime mover 196 is provided that willpermit only one of the electric lamps to actuated its associatedphotoelectric circuit means at any one time.

The electric lamp circuits associated with each of the tanks 138, 140and 142 are identical, and it is thought that a description of one ofsuch circuits will sufllce for all. The electric lamp circuit associatedwith the tank 138 comprises an electric lamp 2% having one terminalconnected through a manual switch 210 to the conductor 192 by a lead212, and having its other terminal grounded through the liquid-levelsensitive switch 176 and the valve and switch assembly 164 in series bymeans of leads 214, 216 and 218. It will thus be seen that when themanual switch 210 is closed, as well as the switch elements of theliquid-level sensitive switch 170 and the valve and switch assembly 164,the electric lamp 288 is lighted. In a similar manner, electric lamps228 and 222 are associated with the tanks 14d and 142, respectively.

As thus far explained, it will be understood that of the electric lamps208, 220 and 222, such lamps will be lighted when the tank associatedtherewith is in readiness to be filled, provided the manual switchesassociated therewith are in their normal closed position.

A photoelectric circuit is associated with each of the electric lamps208, 220 and 222 with such photoelectric circuits includingphotoelectric sensitive elements 224, 226 and 228 so arranged withrespect to the associated electric lamps as to be illuminated therebybut for the interpositioning of an opaque disc 230 between thephotoelectric sensitive elements and the electric lamps.

The opaque disc 230 is rotatable and is operatively connected by meansnot shown to the prime mover 196 so as to be driven by the latter. Theopaque disc 239 is provided with an opening 232 therethrough, the arrangment being such that during rotation of the disc 230, the opening 232 issequentially brought into registry with each of the electric lamps 208,220 and 228 and the individual photoelectric sensitive elementsassociated with such electric lamps, so that only one of thephotoelectric sensitive electric elements may be illuminated by itsassociated electric lamp at any one time.

It is thought that the analogy between the opening 232 of the disc 230and the sector 84 shown in Figure 1 will be readily appreciated;however, it should be pointed out that whenever the prime mover 196 isde-energized with the opening 232 being in registry with a particularelectric lamp and the photoelectric sensitive element associated withsuch lamp, the rotation of the disc 230 will stop with sufficientabruptness that the opening 232 will remain in such registry.

Means is provided in association with each of the photoelectricsensitive elements that will effect energization of the switches 176,178 and 184) upon such photoelectric sensitive element beingilluminated. Such means provided for each of the photoelectric sensitiveelements are identical and it is thought that it will sufiice to describe in detail only such means as is associated with the photoelectricsensitive means 224. Such photoelectric means in association with thephotoelectric sensitive element 224 comprises a common source of D.-C.voltage consisting of a rectifier 234 connected to the conductor 192 bymeans of a lead 236 and connected in series to ground through aninductance 238 and voltage regulator tube 240 by means of leads 242, 244and 246. The lead 242 is grounded through a condenser 248, with thearrangement being such that the lead 244 has a positive potential thatis substantially constant with respect to ground. In this manner platevoltage is supplied to lead 256.

A pentode 250 is provided, the cathode of which is connected to theslider 252 of a variable cathode-bias resistor 254 which is appliedbetween a conductor 256 and the ground, with the conductor 256 beingconnected to the lead 244. The photoelectric sensitive element 224 hasone terminal connected to the conductor 256 and its other terminalconnected by means of a lead 258 to the control grid of the pentode 250,such lead 258 being provided with a grid-leak resistor 260 to ground.The anode of the pentode 250 is connected by lead 262 to the coil 264 ofa sensitive relay whose contact switch 266 is normally open but whichupon energization of coil 264 closes the switch 266. The other side ofcoil 264 is connected to plate-supply lead 256.

The normally-open relay switch 266 is connected in series with the coilof relay 176 in a circuit that starts at lead 192, through lead 268,switch 266, lead 270, the coil of relay 176 and thence to ground.

The operation is such that whenever the lamp 208 is not energized or theopening 232 not in registry therewith, the grid of the pentode 250 isnegative so as to prevent the flow of sufiicient plate current in thelead 262 to cause the relay coil 264 to actuate closure of the relayswitch 266, so that the circuit through the solenoid of the switch 176remains open; however, upon the simultaneous occurrence of the electriclamp 208 being energized and the registry of the opening 232 therewith,the photoelectric sensitive means 224 is energized to render the grid ofthe pentode 250 more positive, whereupon sufiicient plate current flowsthrough the solenoid 264 to actuate closure of the switch 266, therebycompleting the circuit through the solenoid of the switch 1'76.

Similar circuits are provided for use in conjunction with each of thephotoelectric sensitive elements 226 and 228 which include pentodes 272and 274, respectively, which will serve upon their respectivephotoelectric sensitive elements being illuminated to close the switches276 and 278, respectively. It will be evident upon inspection of Figure3 that the switches 276 and 278 bear the same relation to the solenoidsof switches 178 and 180 that the switch 266 has previously beendescribed as hearing to the solenoid of the switch 176.

In order to energize the heaters of the pentodes 250, 272 and 274, asuitable transformer 280 is provided, the primary of which is connectedbetween the conductor 192 and ground, with the secondary terminals 282and 284 of such transformer being connected in parallel to the heatersof the tubes 250, 272 and 274 as shown in Figure 3.

It will be evident that when the heaters of the pentodes have becomecool, as would occur during a power failure or the like, a certainminimum time period is necessary for the heaters to become sufiicientlyheated for operation of the pentodes after the resumption of theapplication of electrical power thereto. Since during the time requiredfor the pentodes to become sufficiently warm for operation none of thesolenoids of the switches 176, 178 and 180 may be energized to open theselector circuit that includes the prime mover 196, means must beproided to otherwise open the selector circuit during this pentodeheating period if it is desiredthat the-prime mover 196 not operateduring such pentode heating period.

Various reasons exist for the desirability of preventing operation ofthe prime mover 196 during the time interval that the pentodes are beingheated to an operative temperature, among which may be mentioned that itis undesirable to have a power failure cause the tank selector andswitcher to switch upon resumption of power from a tank that was in theprocess of being filled at the commencement of the power failure. Inother words, even though the filling of a tank will be interrupted uponthe occurrence of a power failure, it is desired that upon theresumption of power that the apparatus continue to fill the same tankrather than initiate a new search for a tank in readiness to be filledupon the resumption of power. This objective is realized by theprovision of a time-delay tube 286, the coil of which is grounded as at288 and connected to the conductor 192 by lead 290. The switch elementof the time-delay tube 236 is disposed in the lead 202 of the selectorcircuit. The time-delay tube 286 is of the type in which the switchelement thereof is normally open, but which switch element is closed andremains closed after the coil thereof has been energized for apredetermined period of time. In the case of the time-delay tube 286,the time delay provided for the closure of the switch element thereofafter the energization of the coil thereof is somewhat in excess of thetime required for the pentodes .to have been heated to an operativetemperature, a period approximately 15 seconds usually being adequatefor this purpose. Thus, it will be evident that the selector circuitthat includes the prime mover 196 can only be closed during such timethat the pentodes are heated to an operative temperature.

The electrically-actuated inlet valves 152, 154 and 156 are eachgrounded and connected respectively by leads 292, 294 and 296 through asecond pair of contacts of the switches 176, 178 and 189 to theconductor 192.

- Viewed in its broader aspects, the inlet-valve actuating circuits of.he apparatus shown in Figure 3 may, as in the case of the apparatusshown in Figure 1, be considered controlled circuits, with the circuitsthat include the solenoids of switches 176, 178 and 180 being consideredcontrol circuits.

The operation of the tank selector and switcher shown in Figure 3 willbe readily understood, particularly in the light of the hereinbeforedescribed operation of the tank selector and switcher shown in Figure 1.

In its tank selecting function, the prime mover 196 is continuouslyenergized until the same has brought the opening 232 of the disc 230into registry with one of the electric lamps 208, 220 and 222 that isenergized, it being recalled that only such of said electric lamps areenergized as are in association with a tank in readiness to be filled.Upon opening 232 being brought into registry with an energized electriclamp, the associate photoelectric sensitive element is actuated so as tocause its associated pentode to become conductive to such an extent thata solenoid in the plate circuit thereof closes one of the switches 266,276, 278 that causes energizetion of the solenoid of one of the switches176, 178 and 189. Energization of the solenoid of any one of theswitches 176, 178 and 180 causes the blade element of such switch tomove so as to open the selector circuit and at the same time to bridgethe left-hand pair of contacts of such switch that is in series with oneof the electrically-actuated inlet valves. It will thus be seen thatbridging the left-hand pair of contacts of any one of the relays 176,173 and 189 will energize the electrically-actuated inlet valveassociated therewith.

As soon as the tank has been filled to a sufiicient extent to causeopening of the liquid-level sensitive switch (170, 172 or 17s asscci' edtherewith, the electric lamp (2%, 228 or 222) in circuit therewith willbecome deenergized, and through the action of the photoelectricsensitive element (224, 226 or 228.) associated with such i2 electriclamp the related pentode (250, 272 or 274)- be comes sufficientlynon-conductive that the solenoid of whichever of the switches 176, 178and 180 is associated with the tank being filled becomes de-energized,thereupon opening the left pair of contacts, and at the same timeclosing the selector circuit.

It is further evident that should a tank which is in the process ofbeing filled be opened to the discharge line, the opening of its outletvalve such as 164, 166 or 168 and the switch associated therewith willimmediately open the circuit through the associated lamp (208, 220 or222) and in a manner similar to that just described cause deenergizationof the respective relay 176, 178 or 180, thereupon opening its left-handcontacts and closure of its right-hand contacts to effect closure of therespective tank-inlet valve 152, 154 or 156.

The tank selector and switcher shown in Figure 3 incorporates atime-delay tube 364 which is similar to and corresponds in purpose tothe time-delay tube provided in conjunction with the apparatus shown inFigure 1. switch element 3% of the time-delay tube 304 is normally openbut will close in response to continuous energization of the coilthereof for a predetermined time, namely, a period of time equal to orslightly in excess of the selector time cycle. The coil of thetime-delay tube 304 is in electrical parallel with the prime mover 196so as to be energized concurrently therewith, one terminal of the coilof the time-delay tube 304 being grounded as at 3% with the otherterminal of the coil being connected to the prime mover lead 26%} bymeans of lead 310.

it will thus be seen that the time-delay tubes 130 and 364 of both formsof the invention will operate in the same manner with respect to failureof the tank selector and switcher to locate a tank in readiness to befilled from the entire number of tanks associated with such element ofapparatus.

Although only three tanks have been shown in conjunction with each formof the tank selector and switcher, the manner in which the principles ofthe invention may be extended in either form of the invention to controlthe storage of fluid in a lesser or greater number of tanks should beobvious. Three tanks are shown arbitrarily to indicate broadly themanner in which the invention may be associated with a plurality oftanks.

Oil production control equipment Referring again to Figure 1, there isindicated at 312 a schematic representation of an oil well of the typethat requires pumping, and indicated at 314 is an oil well capable offlowing under its own pressure. Although only one of each type of oilwell is illustrated in the drawing, it will subsequently become apparentthat the present invention may be readily adapted for the control of anynumber of either type of oil well indicated.

A common conduit 316 is provided for gathering the oil produced by theoil wells and is provided with oil well branches 318 and 320 coupledindividually to the oil wells 312 and 314. The oil well 312 is providedwith electrically-actuated means indicated at 322 for operating aconventional pump associated with the well 312, and the oil Wellbranches 318 and 320 of the conduit 316 are provided with electricallyactuated oil Well control valves 324 and 326, respectively. Theelectricallyactuated oil well control valves 324 and 326 are of the typein which the valves normally closed when electrically tie-energized butwhich upon electrical energization will open, and are of the samegeneral type as the previously described electrically-actuatedinlet-valves for the storage tanks. Obviously, the electrically-actuatedoil well control valves 32 i and 326 will be of such design as to becapable of positively shutting down production of the oil wellassociated therewith upon deenergization, and may be of any conventionaltype, such as the well As in the case of the time-delay tube 130, the

, 13 known electro-hydraulic type or the solenoid-actuated type.

Energy for the actuation of the valves 324 and 326, as well as thepump-actuating means 322, may be derived from the same power source asthat which actuates the tank selector and switcher, namely, the powerleads 66, 68 and Til. The electrical energy distribution system alsoincludes a control wire 323 that is normally electrically connected tothe power lead 70 through a normally-closed solenoid actuated switch 330whose operation will be described in detail subsequently.

The manner in which pumping wells, such as oil Well 312, are connectedto the power source and are individually controlled is indicated withinthe dashed outline 331. The pump actuating means 322 is electricallyconnected to the power leads 66, 68 and '70 through a triplepole-single-throw switch 332 by means of conductors 334, 336 and 338connected intermediate such means and the switch 332 and conductors 340,342 and 344 connected between the switch 332 and the power leads 66, 68and 7G. The electrically-actuated oil well control valve 324 isconnected between the conductors 334 and 336 by means of leads 346 and348, respectively, the arrangement being such that the means 322 and thevalve 324 are concurrently energized when the switch 332 is closed.Therefore, the valve 324 will be open whenever the pump-actuating means322 is energized, and will be closed whenever the pump actuating means322 is de-energized.

The switch 332 is solenoid actuated, the arrangement being such thatwhenever the solenoid 350 is energized, the switch 332 will be closed,with the switch 332 being bias to the open position whenever thesolenoid 350 is de-energized. Clo-ck controlled switch means isindicated at 352, the electric clock mechanism of which is energized byconductors 354 and 356 connected to the conductors 342 and 3413,respectively. The clock controlled switch means 352 includes a switch358 that will open and close according to a predetermined time schedule,and the switch 358 is arranged in electrical series with the solenoid35d between the conductor 342 and the control lead 328 by means ofconductors 360, 362 and 364. As will be apparent from the drawing, thesolenoid 3563 will be actuated whenever the switch 358 and the switch338 are closed, so that when such switches are closed, the solenoid 359will actuate the switch 332 into closed position and accordingly eflectproduction of the oil well 312; however, whenever either the switch 358is opened by the clock means 352, or the switch 330 is opened in amanner to be subsequently described, the solenoid 358 is de-energizedwhereupon the switch 332 opens thus shutting E or curtailing productionof oil well 312.

As stated previously, any number of pumping wells may be controlledaccording to the principles of the present invention, with each of thepumping wells being connected to the power leads 66, 68 and 79, as wellas the control lead 328 in the manner indicated for the single pumpingwell 312 illustrated. It will be evident that each of such wells mayhave the production thereof individually curtailed through the operationof the individually provided clock-controlled switch means 352 thereof,and that the production of all such pumping wells may be simultaneouslycurtailed by the opening of the switch 330, since it will be evidentthat the switch 330 is in series with the solenoids of each well thatcorresponds to the solenoid 35% illustrated.

Enclosed by dashed lines 366 is the arrangement by which the productionof flowing wells is controlled. Such construction includes aclock-controlled switch means 368 similar to the previously describedclock controlled switch means 352. The clock controlled switch means 368includes a witch 378 controlled thereby to open and close according to apredetermined time schedule. The electrically-actuated oil well controlvalve 326 is arranged in electrical series with the switch 370 to thepower lead 68 and the control power lead 328 by means of conductors 372,374, 376 and 378, the arrangement being such that whenever the switches37% and 333 are closed, the valve 326 is open; however, whenever theclock controlled switch 370 is open, or the switch 330 is open, theelectrically-actuated oil well control valve 326 is de-energized to shutin the flowing well 314.

The electric clock mechanism 379 of the switch-actuating clock means 368is connected between the conductors 374 and 378 in such a manner as tobe energized whenever the switch 330 is closed.

It can thus be seen that with the arrangement illustrated, theclock-controlled switch means 352 operates continuously andindependently of the switch 330, while the clock-controlled switch means368 is energized solely during the periods that the switch 330 isclosed. Optionally, however, the clock mechanism 379 may be electricallyconnected between the conductor 374 and the power lead 74?, rather thanbetween the conductors 374 and 378, so as to be continuously energized.It will thus be apparent that clock-controlled switch means 368 may beso constructed and arranged as to be either dependent, as shown, orindependent upon the operation of switch 330. By the same token, theoperation of the cloclocontrolled switch means 352 may be made dependentupon the closure of the switch 330 by simply connecting the lead 356 tothe control lead 328, rather than the power lead 340.

As in the case of the means for controlling the production of pumpingwells, any number of flowing wells may be connected to the power lead 68and the control power lead 328. Each individual flowing well, such as314, may be shut down according to a predetermined time schedule bymeans of a clock-controlled switch, such as that shown at 368, and allof the flowing wells Will be shut down upon the opening of the switch330.

The operation of the oil production control equipment may be brieflysummarized by stating that the production of each oil well, eitherflowing or pumping, may be individually controlled by the clockcontrolled switch means associated with each well, and in addition theproduction of all oil wells, both pumping and flowing will be shut downwhenever the switch 338 is open. it will be appreciated that theprovision of an oil well control valve in each of the oil well brancheswill prevent oil from a well having a high head pressure from flowinginto a well of lesser head pressure. In addition, it will be appreciatedthat the provision of an oil well control valve in each of the oil wellbranches permits the individual oil well to be operated upon timeschedules independent of the time schedules set up for the other oilwells.

Oil production curtailing apparatus In the usual oil field producinginstallation, the oil produced from the individual wells is passedthrough one or more oil-treating vessels prior to storage thereof, andin Figure 1 such oil treating vessels are indicated as talcing the formof a heater treater 38d, and a separator 382. The oil gathering conduit316 is arranged to discharge into the heater treater 38d through anelectrically-actuated control valve 384, such valve 384 being normallyopen when the same is de-energized, and which will close uponenergization, and the same may be either of the electric motor actuatedtype or the solenoid actuated type for the purpose desired.

The separator 382 receives oil from the conduit 316 through a branchconduit 336 connected thereto. The branch conduit 3% is connected to theconduit 316 upstream of the electrically-actuated control valve 384 andis provided with an electrically-actuated control valve 387 thatcorresponds in type and function to the valve 384.

The heater treater 380 and the separator 382 are provided with gas vents388 and 3% from which separated gas may be passed to a gasolineabsorption plant or other apparatus, not shown, for subsequenttreatment.

The heater treater 380 is provided with a liquid discharge line 391 thatis connected to the header 16 for storage in the tanks 10, 12 and 14.The separator 382 is provided with a liquid discharge line 392 that isconnected to the line 391.

The nature of the crude oil produced determines whether the same shouldbe passed through the heater treater 380 or the separator 382, andaccordingly, suitable valve means, not shown, may be provided in thelines 316, 386, 391 and 392 to selectively direct all the oil movingfrom the line '316 to the line 391 through either the heater treater 330or the separator 382.

The heater treatcr 380 and the separator 382 are provided withliquid-level sensitive switches 394 and 396, respectively. Thearrangement is such that the switches 394 and 396 are normally open, butwill close when the liquid level in the vessel associated therewithrises above a predetermined height. For example, the switch 396 is soconstructed and arranged to close prior to the liquid level in theseparator 382 rising to such a height as to permit liquid to pass intothe gas discharge line 390.

The fundamental purpose of the oil production curtailing apparatus is tocause the switch 330 to open and thereby close down the production ofall the oil wells whenever the tank selector and switcher fails toselect a tank for filling, or whenever either of the vessels 380 or 382becomes excessively filled. In addition, it is the purpose of the oilproduction curtailing apparatus to afford a means for opening andclosing the switch 330 according to a predetermined time schedule. Thesepurposes are realized by the provision of a circuit having a solenoid398 therein, which solenoid 398 is so constructed and arranged withrespect to the switch 330 as to close the latter when energized from itsnormally biased open position.

The solenoid 398 is arranged in electrical series with three separatesets of electrical switch means between the electrical conductors 74 and76, so that the opening of any of such three sets of switch means willcause de-ener gization of the solenoid 398 and the consequent opening ofthe switch 330. Each of the three sets of switch means is normallyclosed and is responsive to open upon the occurrence of one of theabove-mentioned conditions under which it is desired to curtail theproduction of all of the oil wells.

The aforementioned three sets of switch means in association with thesolenoid 398 and means for actuating such switch means comprise a masterclock controlled switch means 4% and solenoid actuated switches 4412 and404.

The switch means 462 includes two pairs of contacts, namely, contacts406 and contacts 498. Switch means 462 also includes a movable bladestructure 419 for simultaneously bridging both pairs of contacts 466 and408, and a solenoid 412 is provided, which upon energizetion willactuate the blade structure 4% to simultaneously open both of the pairsof contacts 406 and 403. The blade structure 416 may be moved to itsnormal position closing both pairs of contacts 496 and 468 by means of asolenoid 414 effective for this purpose when energized.

The switch means 464 is similar to the described switch means 462 andincludes pairs of contacts 416 and 418, a solenoid 429 for actuatingupon energization a blade structure 422 into its normal position closingthe contacts 416 and 41S, and a further solenoid 424 responsive uponenergization thereof to move the blade structure 422 so as to open thepairs of contacts 416 and 418.

The clock-controlled switch means 4% includes a switch 426 that isopened and closed according to a predetermined time schedule and isactuated by an electric clock mechanism diagrammatically illustrated at423. The circuit which includes the solenoid 398 comprises a lead sourceconductor 76.

430 connected to the conductor 74, and leads 432, 434 and 436 connectingthe pairs of contacts 416 and 406 in series between the lead 439 and theswitch 426. In turn, the switch 426 and the solenoid 398 are connectedin series to conductor '76 by leads 437, 438 and 440. It will thus beseen that the solenoid 398 is energized from the conductors 74 and 76only when the switch 426 and the pairs of contacts 406 and 416 areclosed.

The switch 426 is actuated for opening and closing according to a mastertime schedule for all the oil wells by means of the diagrammaticallyillustrated electric clock mechanism 423 that is connected electricallybetween the leads 436 and 449 for continuous energization.

Means is provided for opening the contacts 406 by energizing thesolenoid 412 whenever the switch element 136 of the time delay tube 136is closed. Such means for energizing the solenoid 412 includes in seriesthe switch element 136 and the pair of contacts 408, such electricalcomponents being connected between the conductors 74 and 76 by means ofthe aforementioned lead 446, and leads 442, 444 and 446. It will thus beseen that the blade structure 410 is actuated to open both pairs ofcontacts 466 and 403 by energization of the solenoid 412 whenever theswitch element 136 is closed, thus making the energization of thesolenoid 398 dependent upon the switch element 136 being open.

Means is provided to energize the solenoid 424 and thus open the pair ofcontacts 416 in response to closure of either of the liquid-levelsensitive switches 394 and 396. The electric circuit provided for thispurpose comprises the liquid-level sensitive switches 394 and 396 beingconnected in electrical parallel between one of the contacts 418 and aterminal of the normally closed manual switch 447 by means of a lead 443having branches 450 and 452 connected to the liquid-level sensitiveswitches 394 and 396. The liquid-level sensitive switches 394 and 396are respectively connected by branches 454 and 456 to a conductor 453having connection with the switch 447. The other terminal of the switch447 is connected by a conductor 460 to the power The solenoid 424 isconnected between one of the pairs of contacts 418 and the lead 434, andit will thus be seen that whenever the switch 447 is in its normallyclosed position, closure of either of the liquid-level sensitiveswitches 394 and 396 will complete a circuit through the solenoid 424 toopen the contacts 416, which opening of the contacts 416 will result inde-energization of the solenoid 398.

It will be recalled that the electrically-actuated control valves 384and 387 are of such nature that when deenergized such valves are openedand which close upon energization. The electrical arrangement of suchelectrically-actuated control valves 384 and 337 with respect to thepreviously described liquid-level sensitive switches 394 and 396 is suchthat energization of both of such control valves occurs whenever eitherone of the liquidlevel sensitive switches 394 and 396 is closed with theswitch 447 being also closed. Such electrical arrangement comprises theelectrically-actuated control valves 384 and 387 being connected inelectrical parallel between the conductor 74 and the lead 448, by meansof the lead 430 that is connected through branches 462 and 464 to thevalves 384 and 337, respectively, the valve 384 being connected to thelead 443 by a lead 466, and the valve 387 having connection to the lead448 by means of a branch lead 463.

The electrically-actuated control valves 384 and 387 are arranged incircuit in such manner that with the manually-operated switch 447 in itsnormally closed position, closure of either of the liquid-levelsensitive switches 394 and 396 will complete a circuit through thevalves 334 and 337 to energize both of them whereupon they will move tothe closed position.

In View of the foregoing, it will be seen that closure of either of theliquid-level sensitive switches 394 or 396 will not only causede-energization of the solenoid 398, but will also cause energization ofboth of the control valves 384 and 387.

It will be appreciated that after either of the solenoids 412 or 424have been energized to cause an opening of their respective switches,such switches will remain open until either manually closed, or prefrably by means of the energization of the solenoids 414 and 420 that areprovided for this specific purpose. The solenoid 414 is connected bymeans of leads 476 and 472 to leads one and 474, respectively, with thelead 472 including a normallyopen switch or reset button 476. The leads46d and 4-74 are connected to the conductors "i6 and 74, respectively,whereby closure of the switch 476 will cause energization of thesolenoid 414, and consequently the closing of the contacts 406 and 408.The solenoid 426 is connected between the leads 464} and 474 in a mannersimilar to that of the solenoid 41 i, and is provided with anormallyopen switch or reset button 478, whereby the circuit through thesolenoid 426 between the conductors 74 and 76 may be completed forcausing the blade structure 422 to move into a position closing thecontacts 416 and 418.

It will thus be apparent that upon either of the solenoids 412 and 424having once been energized, the solenoid 393 will remain continuouslyde-energized, and in order to resume operation of the apparatus it isnecessary for the operator to physically depress the appropriate resetbutton, either 476 or 478. This is an important operational advantage inthat the operator is apprised of of the fact that some condition hasarisen causing an unscheduled curtailment of production, such as theseparator becoming over full, and he is given an opportunity to remedythe cause of the ditl'iculty prior to attempting to resume production.

Of course, it would be a simple matter to so modify the illustratedconstruction so that the above-mentioned physical resetting operationwould not be necessary, but such modification would permit a badcondition such as the discharge line 392 of the separator becomingclogged to become more aggravated without the operator becoming aware ofthe fact. Although not shown, such modification could simply take theform of mechanically biasing the blade structures 410 and 422 towardsthe switch closing positions. In addition, the solenoid 412 would beconnected directly to the lead 444 rather than through the pair ofcontacts ans, while the solenoid 424 would be connected directly betweenthe leads 430 and 448, whereby the solenoids 412 and 424- would beenergized solely during the time the switch element 136 and one of theswitches 394 and 396 are closed, respectively. Whenever it is desired toprevent energization of the solenoid 424 and the valves 384 and 337irrespective of the closure of either of the switches 394 and 396, thismay be accomplished by opening the switch 447. For example, the switch447 may be opened when it is desired to manually dump the separator 382upon the latter becoming overfuil.

Operation The operation of the tank selector and switcher, as well asthe o eretion of the oil production control equipment and oil productioncurtailing apparatus have already been individually described above. Thecom'bined'operation of these three units will now he described.

Referring to the structure shown in Figure l for an explanation of theover-all operation of the invention, the tank selector and switcher willoperate upon the completion of filling of any of the tanks to select orlocate a further tank in readiness to be filled and upon locating such afurther tank, the inlet valve of such tank is opened to permit thefilling thereof. In the event that the tank selector and switcher failsto select or locate a tank in readiness to be filled within a timeinterval equalling or slightly in excess of the selector time cycle, the

18 switch element 136 of the time-delay tube is closed. Such closure ofthe switch element results in the energization of the solenoid 412 andthe consequent de-energization of the solenoid 3% to effect thereby theopening of the control switch 336. Opening of such switch 333 results inshutting down all the oil wells producing oil for storage in the tankbattery.

In addition to the switch 338 opening as a consequence of the allure ofthe tank selector and switcher locating l tank in readiness to befilled, the switch 3% is opened in accordance with a predetermined timeschedule set by the clock controlled switch means 4%. Furthermore,overfilling of either of the oil treating vessels and 332 will result inopening the switch 330 in a manner similar to failure of the tankselector and switcher.

It is to be noted that de-cnergizatiou of the solenoid and theconsequent opening of the switch 33% whenever occurring as a result ofthe failure of the tank selector or switcher to locate a tank inreadiness to be filled, or the overfilling of either of the oil treatingvessels 33D and 382 will necessitate resetting of the switch means 4&2vor 464, respectively, by the use of the reset buttons 476 and 478,respectively; however, such resetting operation is not necessary whenthe de-ener ation of the solenoid 392i occurs as the result of theopening of the switch 426.

The individual oil wells, wh ther or the flowing or pumping type, willoperate in accordance with individual predetermined productionschedules, while being subject to the over-all control maintained by theopening and closing of the switch 330 in accordance with thedc-encrgization and energization of the solenoid The alternative form oftank selector and switcher shown in Figure 3 may be readily substitutedfor that shown in Figure 1, it being thought evident that the manner ofsuch substitution will be evident to those skilled in the art' However,in order to avoid any difficulty on the part of those seeking to realizethe advantages or" the invention for using the modified form of tankselector and switcher, the manner of such substitution will be set forthin some detail.

The condenser 74 shown in Figure 1 would be connected to the componentsof the modified form of tank selector and switcher shown in Figure 3 inthe same manner as conductor 192 is shown connected to such components.The conductor 76 would be "rounded in the manner as shown at 194 inFigure 3, and the components of the modified tank selectors and switcherwould be grounded in the same manner as shown in Figure 3, oralternatively, the components shown ground ed in Figure 3 could beconnected directly to the conductor 76. The lead 444 shown in Figure 1would be connected to one terminal of the switch element 3% of thetimed-clay tube and the other terminal of the switch element 386 wouldbe connected to the conductor 74.

An advantage of the invention resides in how well the same is adaptedfor the application of indicator lights thereto. For example, indicatorlights may be provided to indicate which tank is being filled, and whichtanks, if any, are in readiness to be filled. Such indicator lights areshown in Figure l with respect to tank Elli, it being evident thatsimilar provision may be made for each tank. Indicator light 48% isconnected between the leads 129 and 124'- so as to be in parallel withthe valve 32 and therefore be energized concurrently therewith. Thus,illumination of indicator light indicates that tank is being tilled.

Obviously, the indicator light may be located adjacent the switch 5-3,or adjacent the tank fit as desired, or two lights at such positions maybe employed with a minimum of wiring required.

indicator light 482 is connected between the leads and 112, so that thesame is energized whenever tank id is in the process of being filled oris in readiness to be filled. Accordingly, the status of tank it) in sofar as 19 the automatic operation of the equipment is concerned may befully ascertained upon visual inspection of indicator lights 48!) and482.

The form of tank selector and switcher illustrated in Figure 3 islikewise adapted for the attachment of indicator lights thereto. Anindicator light, not shown, may be connected between either lead 270 orlead 292 and ground for the same purpose of indicator light 480described in connection with Figure 1. Similarly, an indicator light,not shown, may be bridged across the electric lamp 208 for the samepurpose that the indicator light 482 is provided with the form of theinvention shown in Figure 1.

The production curtailing apparatus may be provided with indicatorlights to indicate the failure of the tank switcher to select a tank andto indicate the overfilling of either of the vessels 380 and 382. Anindicator light 484 is connected between the leads 440 and 444 so as tobe energized whenever the switch element 136 is closed, or in otherwords. whenever the tank switcher fails to locate a tank for filling.

Another indicator light 486 is'connected between the leads 430 and 448so as to be energized whenever either o the switches 394 and 396 areclosed with the switch 44-7 being in its normally closed position.

The invention is of course subject to numerous variations within the sirit thereof that will readily occur to those skilled in the art. Exemlary of such variations, a slight change in electrical circuitry willrender the solenoid 412 ca able of curtailing oil well production onlywhen the switch 4-26 of the master clock control means 404 is closed.Such change involves merely connecting the lead 442 to the lead 436instead of the lead 440, so that the solenoid 412 is in series with theswitch 426.

In the light of the foregoing. the structure and operation of theinvention will be fully understood, and further explanation is thoughtto be unnecessary. The invention has been set forth in considerabledetail in the interest of conveying a full and complete understandingthereof, and such detailed description should not be considered asunduly limiting the invention, but rather the appended claims should bereferred to in order to ascertain the actual scope of the invention.

What I claim is:

1. In the combination of means for supplying fluid to a multiple-tankbattery and automatic electric control apparatus for sequentiallyfilling selected tanks of such battery with supplied fluid to apredetermined extent that includes tank selecting means operable uponthe filling of one tank to select automatically the tank next to befilled with such tank-selecting means having an electric circuit that isclosed solely during the interval between the filling of one tank untilthe tank next to be filled is selected, the improvement comprisingelectrical means responsive to substantially continuous closure of saidelectric circuit for a predetermined period of time to curtail thefunctioning of the first mentioned means.

2. The combination of claim 1, wherein said electrical means includes atime-delay switch actuating means connected to said electric circuit.

3. Apparatus for controlling the storage of a fluid in a multiple-unitstorage facility and for controlling the supply of fluid to such storagefacility comprising, an electric power source, a plurality ofnormally-open valve actuating circuits connected to the power sourceeach including an electrically operated valve actuator, anormally-closed selector circuit connected to the power source, meansfor maintaining the selector circuit open whenever any one of thevalve-actuating circuits is closed, control means associated with eachvalve-actuating circuit for selectively preventing such circuit beingclosed, circuit closing means including a prime mover in said selectorcircuit, said circuit-closing means being effective during the time thatthe selector circuit is closed to sequentially close the valveactuatorcircuits that are not denied closure by said conthe supply of fluid tothe storage facility, means effective upon substantially continuousclosure of said selector cit-- cuit for a predetermined period of timeto cause the last mentioned means to curtail the supply of fluid.

4. The combination of claim 3, wherein said circuit closing meanscomprises a photoelectriccircuit means as sociated with eachvalve-actuating circuit and connected to the power source for closingthe valve-actuating circuit, each of said photoelectric circuitsincluding a light-sensitive element and a normally energized electriclight source arranged to illuminate such element, light-maskin; meansfor masking all but a selected one of the lightsensitive elements, andmeans including said prime mover formoving said masking means tosequentially unmask the light-sensitive elements.

5. The combination of claim 3, wherein said circuit closing meanscomprises a plurality of electric circuits corresponding in number tothe valve-actuating circuits, selector switch means connected to theprime mover for actuation thereby, each of said electric circuits beingconnected to the power source through the selector switch means andincluding means effective during the time that such electric circuit isclosed to maintain one of the valveactuating circuits closed.

6. Apparatus for controlling oil well production and the storage ofproduced oil in a multiple-tank battery comprising, an electric powersource, a plurality of normally-open valve actuating circuits connectedto the power source each including an electrically-operated valveactuator for actuating a tank-inlet valve, a selector switch, anormally-closed selector circuit connected to the power source andincluding electrical means for actuating the selector switch, a controlcircuit associated with each valve-actuating circuit with each controlcircuit being connected to the power source through the selector switchand including in series a control switch means and means operable uponenergization to actuate closure of its associated valve-actuatingcircuit and also actuate opening of the selector circuit, electricalmeans for controlling oil well production including switch meansefiective upon actuation to cause curtailing of oil well production, andmeans responsive to the substantially continuous closure of the selectorcircuit for a predetermined time to actuate the last mentioned switchmeans.

7. The combination of claim 6, wherein the last recited means includes atime-delay switch actuating means connected to said selector circuit.

8. The combination of claim 6, including electric clock means foractuating said switch means.

9. A control system for controlling the production of a plurality of oilwells and for controlling the storage of oil produced thereby in amultiple-tank battery, said system comprising a fluid conduit providedwith a plurality of oil well branches and a plurality of tank branches,each of said oil well branches being provided with anelectricallyactuated oil well control valve normally energized to openposition, each of said tank branches being provided with anelectrically-actuated tank'inlet valve that is normally de-energized andin closed position, automatic electrical means for selecting andsequentially energizing tank-inlet valves of tanks in readiness to befilled, such automatic electrical means including an electric circuitthat is energized substantially solely during the intervals that alltank-inlet valves are cle-energized, and means responsive to saidelectric circuit remaining substantially continuously energized apredetermined time to de-energize all of said oil well control valves.

10. The combination of claim 9, wherein said last named means includes atime-delay switch actuating means connected to said electric circuit.

11. A control system for controlling the production of a plurality ofoil wells and for controlling the storage of oil produced thereby in amultiple-tank battery, said system comprising a fluid conduit providedwith a plurality of oil well branches and a plurality of tank branches,at

least some of the individual oil well branches being provided with anelectrically-actuated oil well control valve normally energized to openposition, at least some of the individual oil well branches beingprovided with a normally-energized electrically-actuated oil well pump,each of said tank branches being provided with an electricallyactuatedtanloinlet valve that is normally de-energized and in closed position,automatic electrical means for selecting and sequentially energizingtank-inlet valves of tanks in readiness to be filled, such automaticelectrical means including an electric circuit that is energizedsubstantially solely during the intervals that all tank-inlet valves aretie-energized, and means responsive to said electric circuit remainingsubstantially continuously energized a predetermined time to de-energizeall of said electrically-actuated oil well control valves and oil wellpumps.

12, A control system for controlling the production of a plurality ofoil wells and for controlling the storage of oil produced thereby in amultiple-tank battery, said system comprising a fluid conduit providedwith a plurality of oil well branches and a plurality of tank branches,an oil-treating vessel interposed in said conduit intermediate said oilwell branches and said tank branches, each of said oil well branchesbeing provided with an electricallyactuated oil well control valvenormally energized to open position, each of said tank branches beingprovided with an electrically-actuated tank-inlet valve that is normallydie-energized and in closed position, automatic electrical means forselecting and sequentially energizing tank-inlet valves of tanks inreadiness to be filled, such automatic electrical means including anelectric circuit that is energized substantially solely during theintervals that all tank-inlet valves are de-energized, and electricalcontrol means responsive to said vessel being filled above apredetermined level and also responsive to said electric circuitremaining substantially continuously energized a predetermined time toale-energize all of said oil Well control valves.

13. A control system for controlling the production of a plurality ofoil wells and for controlling the storage of oil produced thereby in amultiple-tank battery, said system comprising a fluid conduit providedwith a plurality of oil well branches and a plurality of tank branches,an oil-treating vessel interposed in said conduit intermediate said oilwell branches and said tank branches, an electrically-actuated oil wellcontrol valve normally energized to open position in each of the oilwell branches, an electrically actuated flow control valve normallydeenergized and in open position in the conduit intermediate the oilwell branches and said vessel, each of said tank branches bein, providedwith an electrically-actuated tank-inlet valve that is normallyde-energized and in closed position, automatic electrical means forselecting and sequentially energizing tank-inlet valves of tanks inreadiness to be filled, such automatic electrical means including anelectric circuit that is energized substantially solely during theintervals that all tank-inlet valves are (lo-energized, and electricalcontrol means responsive to said vessel being filled above apredetermined level to de-energize all of said oil control valves and toenergize said flow control valve, said control means being also responsive to said electric circuit remaining substantially continuouslyenergized a predetermined time to de-energize all of said oil wellcontrol valves.

14. In combination with apparatus for controlling oil well productionand the storage or" oil therefrom in a tank battery of the type thatoperates to sequentially fill empty tanks and wherein actuating electricpotential is applied upon one tank becoming full to an electrical devicethat automatically selects the tank next to be filled with suchpotential being removed upon completion of such selection;electrically-operated time-delay means arranged to be concurrentlysubjected to an electrical potential with said electrical device forcurtailing oil well production.

15. In apparatus for controlling the introduction of fluid into amultiple-unit storage facility, an electric power source, a plurality ofnormally-open valve-actuating circuits connected to the power sourceeach including an electrically-operated valve actuator, a normallyclosedselector circuit connected to the power source, means for maintainingthe selector circuit open when ever any one of the valve-actuatingcircuits is closed, control means associated with each valve-actuatingcircuit for selectively preventing such circuit being closed, andcircuit-closing means including a prime mover in said selector circuit,said circuit-closing means being effective during the time that theselector circuit is closed to sequentially close the valve-actuatorcircuits that are not denied closure by said control means.

16. The combination of claim 15, wherein said circuit closing meanscomprises a photoelectric circuit means associated with eachvalve-actuating circuit and connected to the power source for closingthe valve-actuating circuit, each of said photoelectric circuitsincluding a light-sensitive element and a normally-energized electriclight source arranged to illuminate such element, lightmasking means formasking all but a selected one of the light-sensitive elements, andmeans including said prime mover for moving said masking means tosequentially unmask the light-sensitive elements.

17. The combination of claim 16, wherein said control means includes anormally-closed electric switch means in series with each light sourcefor breaking the circuit through the light source.

18. The combination of claim 17 with a detecting means in associationwith each of the electric switch means for opening the latter.

19. The combination of claim 15, wherein said circuitclosing meanscomprises a photoelectric circuit means associated with eachvalve-actuating circuit and connected to the power source for closingthe valve-actuating circuit, each of said photoelectric circuitsincluding a lightsensitive element and a normally-energized electriclight source arranged to ilurninate such element, light-masking meansfor masking all but a selected one of the lightsensitive elements, meansincluding said prime mover for moving said masking means to sequentiallyunmask the light-sensitive elements, said photoelectric circuit meansincluding an electric amplifier tube having a heater element electricallconnected to the power source, and means for preventing operation of theprime mover for a predetermined time after the power source isoperative, whereby the heater will be effectively heated before theprime mover can operate.

20. The combination of claim 15, wherein said circuitclosing meanscomprises a plurality of electric circuits corresponding in number tothe valve-actuating circuits, selector switch means connected to theprime mover for actuation thereby, each of said electric circuits beingconected to the power source through the selector switch means andincluding means effective during the time that such electric circuit isclosed to maintain one of the valve-actuating circuits closed.

21. The combination of claim 15, wherein said circuitclosing meanscomprises a plurality of electric circuits corresponding in number tothe valve-actuating circuits, selector switch means connected to theprime mover for actuation thereby, each of said electric circuits beingconnected to the power source through the selector switch means andincluding means eitective during the time that such electric circuit isclosed to maintain one of the valve-actuating circuits closed, saidcontrol means comprising an electric switch means in each of theelectric circuits for opening the latter.

22. The combination of claim 15, wherein said circuitclosing meanscomprises a plurality of electric circuits corresponding in number tothe valve-actuating circuits,

greases" selector switch means 'conne ted to theprime mover foractuation thereby, eachof said electric circuits being connected to the'power source through the selector switch means and including meanseifective during the time that such electric circuit is closed tomaintain one of the valve-actuating circuits closed, said control meansincluding electric switch means in each of the electric circuits, anddetecting means for actuating said electric switch means.

23. In apparatus for controlling the introduction of fluid into amultiple-unit storage facility, an electric power source, a plurality ofswitch means each including first and second pairs of terminals andterminal bridging means normally bridging the first pair of terminalsfor selectively bridging the pairs of terminals, a selector circuitconnected to the power source and including in. series all of the firstpairs of terminals, a valve-actuating circuit associated with each ofsaid switch means and including in series the second pair of terminalsof such switch means and an electricallyoperated valve actuator, anormally-open electric circuit associated with each of said switch meansand connected to the power source and including means eifcctive duringenergization to cause one of the bridging means to selectively bridgeone of the second pair of terminals, and means for selectively closingsaid electric circuits including a prime mover in the selector circuit.

24. The combination of claim 23, wherein the last mentioned meansincludes a selector switch through which each of the electric circuitsis connected to the power source, a control switch in each of theelectric circuits, and means operatively connecting the prime mover tothe selector switch.

25. The combination of claim 23, wherein the last mentioned meanscomprises photoelectric circuit means associated with each electriccircuit and connected to the power source for closing the electriccircuit, each of said photoelectric means including a ligh -sensitiveelement and a normally-energized electric light source arranged toilluminate the light-sensitive element, a control switch in series witheach electric light source, masking means for selectively masking allbut one of the lightsensitive elements from its associated electriclight source, and means operatively connecting the prime mover to themasking means.

26. In apparatus for controlling the introduction of fluid into amultiple-unit storage facility, an electric power source, a plurality ofnormally-open valve actuating circuits connected to the power sourceeach including an electrically-operated valve actuator, a selectorswitch, a normally-closed selector circuit connected to the power sourceand including electrical means for actuating the selector switch, acontrol circuit associated with each valve-actuating circuit with eachcontrol circuit being connected to the power source through the selectorswitch and including in series a control switch means and means operableupon energization to actuate closure of its assosociated valve-actuatingcircuit and also to actuate opening of the selector circuit.

27. The combination of claim 26, including detecting eans adapted todetect a predetermined condition of readiness of a storage unit toreceive fluid for actuating each 01 said control switch means.

28. In apparatus for controlling the introduction of liquid from acommon source into a plurality of storage tanks each of which isprovided with an inlet valve and an electrical actuator therefor, aliquid-level detector and a switch actuated there-sy, and an outletvalve equipped with an electric switch adapted to open and closetherewith; the improvement comprising a power source, a plurality ofnormally-open inlet-valve actuating circuits each connected to the powersource and including one of the electrical inlet-valve actuators, arotary selector switch, a control circuit associated with each inletvalve actuating circuit with such control circuits being connected tothe power source through the selector switch, each of the controlcircuits including in series one of the switches actuated by aliquid-level detector, one of the switches with which the outlet valvesare equipped and electrically operated means for closing one of theinlet-valve actuating circuits, a normally-closed selector switchactuating circuit connected to the power source and includingelectrically-operated means for actuating said selector switch, andmeans for openin the selector switch actuating circuit Whenever any oneof the inlet-valve actuating circuits is closed.

29. The combination of claim 28 including a further electric switch ineach of the control circuits and in series with the other switches insuch control circuit.

30. The combination of claim 15 including a further electric switch, andmeans for actuating such further electric switch upon substantiallycontinuous closure or" the selector circuit for a predetermined time.

References Cited in the tile of this patent UNITED STATES PATENTS2,024,179 Morrow Dec. 17, 1935 2,115,827 Powell May 3, 1938 2,144,033Root Ian. 17, 1939 2,572,621 Hobson Oct. 23, 195.? 2,594,181 Kliegl etal Apr. 22, 1952 2,605,789 Nance Aug. 5, 1952 2,668,249 Nagel Feb. 2,1954

